Earth boring apparatus



Feb. 27, 1962 H. J. TRocHE EARTH BORING APPARATUS 4 Sheets-Shea?I 1Filed July 7. 1959 I ll lll l/ INVENTOR. Henman J. ll'aoun Feb. 27, 1962H, J, TRocHE EARTH BORING APPARATUS 4 Sheets-Sheet 2 Filed July 7, 1959INVENTOR. HeRMnN J. Taocus Feb. 27, 1962 H. J. TROCHE EARTH BORINGAPPARATUS 4 Sheets-Sheet 5 Filed July '7, 1959 xk@ i.

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INVENTOR.y

HERMRN J. Tszoc'us` .BY A y 782.42' Klamm] c5 Ohio Fiied ll'uly 7, 1959,Ser. No. 825,610 Claims. (Cl. 175-201) This invention relates generallyto power operated earth boring apparatus, and more particularly to amultiple-speed, geared earth boring apparatus adapted for mounting on avehicle for ready portability.

There has been a long felt need in the art of portable earth borers fora multiple-speed, geared unit which is rugged and compact inconstruction and which possesses multiple digging speeds, including amedium torque, no1'- mal digging speed for conventional type soilconditions, and a higher torque, slower digging speed for use under morediicult digging conditions, such as harder soils, etc., and whichembodies some means for ready removal of borings from the auger or earthborer tool, after the auger has been retracted from the hole producedthereby. Many types of soils, such as the clays, are extremely difcult,especially when wet, to dislodge from the auger of known earth boringapparatus. Prior art arrangements of portable type earth borers are alsocomparatively difcult to actuate and control, thereby necessitating theuse of an excessive number of personnel for operating the same.

The present invention, provides a compact, fluid powered, geared earthboring apparatus which possesses the aforementioned multiple diggingspeeds for effective use under varying soil conditions, and whichincorporates means for providing a novel spinning speed for the auger,for effectively throwing-oil borings which have adhered thereto afterwithdrawal thereof from the hole, and which includes a novel arrangementof control or shifting mechanism for selectively changing to one or theother of the digging speeds, and for selectively initiating the spinningspeed of the auger, irrespective of the digging speed at which theapparatus is set to operate. In one embodiment of the invention, anearth boring apparatus of the above type is provided wherein thetransmission digging speed gear sections and their associated housingportions, which provide for the multiple digging speeds of theapparatus, are detachably connected together as individual, separableunits, such apparatus being readily changed over to a single diggingspeed type earth borer, instead of the multiple digging speed type, bysimply removing one complete speed change gear section and itsassociated housing from the transmission assembly, to thereby provide alower cost, relatively smaller size unit and without the necessity ofredesigning or cornpletely reconstructing the operating parts of theapparatus. l

Accordingly, an object of the invention is toprovide an improved,compact, multiple-speed earth boring apparatus for use primarily as aportable unit.

Another object of the invention is to provide an earth boring apparatusof the latter type which incorporates means for providing a readilyactuatable spinning speed for the auger of the apparatus, to effect athrow-oft" of borings which may tend to adhere to the auger afterWithdrawal thereof from the hole produced thereby.

A further object of the invention is to provide an earth boringapparatus of the latter type including readily actuatable andcontrollable gear shifting or control apparatus, for shifting into thedesired digging or spinning speed position, and including means foryieldably retaining the gear shifting apparatus in the desired diggingspeed setting.

ZZQ Patented Feb. 2'?, i962 A still further object of the invention isto provide earth boring apparatus of the latter type in which thedigging speed gear'sections for the multiple digging speeds of theapparatus are detachably connected together as individual, separableunits, so that certain of such gear units can be readily removed fromthe apparatus without redesigning or materially reconstructing theapparatus, to thereby provide a lower cost single digging speed unit ifso desired.

Other features and advantages of the invention will be apparent from thefollowing description taken in conjunction with the accompanyingdrawings wherein:

FIG. 1 is a side elevational View of an earth boring apparatus of theinvention carried by a movable derrick structure mounted on a utilitytype vehicle; in full lines there is shown an operative position of thederrick and, associated earth boring apparatus and in dotted lines thereis illustrated an inoperative, clamped position of the auger withrespect to the derrick, and in dot-dash lines the inoperative carriedposition of the derrick or boom and earth boring apparatus on thevehicle is illustrated.

FIG. 2'is a fragmentary, top plan view of the boom and earth boringapparatus shown in FIGURE l, with the utility vehicle having beenremoved in the interests of simplicity.

FIG. 3 is an enlarged, partially sectioned, elevational view of oneembodiment of the speed change power transmission unit for the auger ofthe earth boring apparatus, and is of the afore-mentioned type whereinthe digging speed change gear sections are detachably connected togetheras individual, separable units, so that one of the gear sections and itsassociated housing portion may be readily removed from the transmissionunit, for providing a lower cost, more compact, single digging speedunit.

FIG. 4 is a horizontal sectional view taken substantially along theplane of line 4-4 of FIG. 3 looking in the direction of the arrows.

FIG. 5 is a horizontal sectional view taken substantially along theplane of line 5 5 of FIG. 3 looking in the direction of the arrows.

FIG. 6 is a horizontal sectional view taken substantially along theplane of line 6-6 of FIG. 3 looking in the direction of the arrows.

FIG. 7 is a horizontal sectional view of one of the shiftable couplingcollar elements of the transmission gear train which lprovides fordriving the transmission at its various speeds, and is particularly usedfor initiating the spinning speed for the auger.

FIG. 8 is a vertical sectional view of another of the shiftable couplingcollar elements of the transmission gear train, and is particularly usedfor initiating one or the other of the digging speeds for the auger.

FIG. 9 is an enlarged, fragmentary, side elevational view of the diggingspeed control lever used to actuate the coupling collar element of FIG.8, and illustrates the position of such lever when the FIG. 8 collarelement is in poistion to provide a high torque low digging speed forthe auger; in dot-dash lines the lengthwise axis of the control lever isshown if such lever is moved to actuate the FIG. 8 coupling collarelement into its other coupling position to provide a medium torquenormal digging speed for the auger.

FIG. 10 is a section view taken substantially along the plane of linelil-10 ofv FIG. 9, looking in the direction of the arrows, and yieldablyretaining Vthe control lever of FIG. 9 in its selected position.

FIG. ll is an enlarged, sectional, elevational view of a ,i modifiedarrangement of a speed change gearedtransmisparticularly illustrates themeans for sion unit for driving the auger of the earth boring mechanism.

FIG. 12 is a fragmentary, enlarged partially sectioned elevational viewof the digging speed control lever of the modification of FIG. 1l forshifting or changing the digging speed of the auger, together with themeans for yieldably retaining such control lever in the desired setting.

FIG. 13 is a diagrammatic illustration of the operational eiect of themeans illustrated in FIG. l2 for yieldably retaining the digging speedcontrol lever in its desired or positioned setting.

Referring again to the drawings and in particular to FIGS. 1 and 2thereof, there is illustrated a utility type wheeled vehicle on which ismounted a boom or derrick 12 hinged as at 14 to the vehicle for swingingmovement in a generally vertical plane. Fluid powered reciprocal motorunits 15 may be provided on either side of the boom structure foractuating the latter in its vertical plane movement. An earth boringtool in the form of a power operated auger 16, is pivotally carried bythe derriclt 12 for swinging movement in a generally vertical plane toprovide for swinging movement of the earth boring tool .with respect tothe derriclc structure. An arm 18 is pivotally connected to the boom asat 20 and at its lower end pivotally supports, as at 22, the speedchange power transmission unit 24 of the earth boring apparatus, andwith which this invention is particularly concerned.

A fluid-powered, double acting, reciprocal type motor unit 26 may beprovided for adjusting the position of the earth boring tool withrespect to the boom and in a vertical plane. Motor unit 26 is pivotallyconnected as at 2S to cross member 30 of the boom and at the other endthereof is pivotally connected as at 32 to the arm 18, supporting theearth boring apparatus. As shown in dotted lines in FIG. l, the earthboring apparatus may be folded up to an inoperative position where itextends generally parallel to the boom structure, and may be detachablyclamped or fastened thereto as at 36 for convenient handling, afterwhich the boom 12 may be pivoted about its pivotal connections 14 on thevehicle to an inoperative carried position overlying the vehicle 1t),and as shown in phantom lines in FIG. 1.

Referring now in particular to FIGS. 1 and 3, the aforementioned speedchange power transmission unit 24 comprises a sectional housing orcasing 38 having an upstanding carrier or handle portion 4t) whichrotatably mounts a cross sleeve 40a at its upper end for swingingmovement of the transmission unit in a plane generally transverse to thevehicle 10. Cross sleeve 40a is provided with an upstanding shankportion 405 which is pivotally connected as aforementioned at 22 to thelower endof supporting arm 18. In FIG. 3 of the drawings, carrierportion 4G and associated cross sleeve 40a and shank portion 4Gb havebeen rotated 90 out of their actual position with respect to theunderlying transmission gear train, the actual positional relationshipbeing correctly shown in FIG. 1, so as to better illustrate the highspeed, uid powered, rotary and preferably reversible motor unit 41mounted on the-top or cover plate 43 of the transmission housing 38, aswell as the positions of the control levers for shifting thetransmission into its various speed settings.

Motor unit 41 which is of conventional well known type is connected bysuitable feed and return lines via ports 41a to a pump unit (not shown)mounted on the vehicle 10, and suitable valve means (not shown) ofconventio'nal well known type may be provided for controlling'the ow anddirection of pressurized uid to the motor, and in a manner well known inthe art. The' aforementioned pump may be powered from a separate sourceof power such as an engine mounted on the vehicle, but is preferablyoperatively coupled to the main power plant orV propelling engine'of thevehicle for actuation ofthe pump and in a manner well known in the art.Such pump may also' be operatively connected to the other fluid poweredmotor units of the apparatus, such as units 15 and 26, for actuationthereof in the conventional manner well known in the art.

The output shaft 42 of rotary motor unit 41 has a sun gear 44 securedthereto as at 44a, such sun gear being in meshing relation with planetgears 46 (FIG. 4) rotatably mounted as at 46a on rotatable planetarycarrier structure 4S. Planetary gears 46 are in meshing relation with aninternal ring gear 50 secured to the transmission housing, as by meansof dowel pins 50a. Sun gear 44, planetary gears 46 and associatedcarrier structure 48, and ring gear 50 thereby provide a rst speedreduction unit 51 for the transmission.

Planetary carrier structure 48 has a speed change gear 52 secured to itslower end for rotation therewith and with respect to transmission shaftmember 54. A fixed, change gear 56 is disposed adjacent gear 52 and issecured as at 56a to shaft 54, and an axially movable or shiftablesliding change gear collar 53 (FIG. 7) having internal gear teeth 60 and62 on opposite ends thereof is provided, such coupling collar 58 beingmovable from the coupling relation shown in FIG. 3 between gear 52 andgear 56 tixed to shaft 54, into coupling relation between gear 52 andsun gear 64 rotatably mounted with respect to shaft 54.

Shaft 54 is journaled for rotation with respect to housing 38, as bymeans of bearings 66, and has its output end 68 secured to shank 7i) ofthe auger 16, the latter securement in the arrangement illustrated beingaccomplished by means of sleeve 72 secured to the upper end of augershank 70 and a bolt and nut assembly 74 extending through complementaryopenings in the output shaft 68 and sleeve 72. Thus it will be seen thatwhen the coupling collar 58 is in coupling relation between gear 52 andgear 56, the latter being fixed to shaft 54,

such shaft is rotated at a relatively high speed depending on the speedreduction of the motor unit 41 due to the planetary speed reduction unit51. This relatively high speed is the aforementioned spinning speed forthe auger and is adapted for use to throw off borings that may havestuck or adhered to the auger after withdrawal thereof from the drilledhole.

The mechaniss for actuating change gear collar S8 will now be described:

The collar 58 has a circumferentially extending groove 76 (FIGS. 3 and5) which receives therein a shifter fork element 78 (FIG. 5). Shifterfork element 78 is secured as at 78a to a shaft or rod 8i) extendinghorizontally and transversely of the casing 38 and which is rotatablymounted with respect thereto, as at 86a. A cap 82 is secured as at 82ato one end of shaft 86 exterior-ally of casing 38, and a torsion springelement 84 is secured at one end to the cap 82 and at the other end tocasing 38 for yieldably resisting rotary movement of the shaft 80. Theother end of the shaft has an operating handle 86 secured thereto forselectively actuating shaft 80 and associated shifter fork 78.

-The torsion spring 84 is so disposed with respect to the shaft 8i) andcasing 38 that the sliding change gear collar 58 is normally maintainedout of coupling relation with gear 56 fixed to shaft 54. In other words,the position of collar 58 and associated control lever 86 illustrated inFIG. 3 is that when the handle or lever 86 has been pivoted upwardlyfrom its normal position to rotate the shaft 8d against the resistanceof spring 34 to move gear collar S8 into coupling relation between gear52 and fixed gear Sti.v It will be seen therefore that the transmissionis normally not in condition for providing the spinning speed to theauger, but such spinning speed is only provided upon pivoting of controlhandle 8,6 upwardly.

Referring now to FIG. 1, in order to actuate handle 86 from ground levelto provide the aforementioned spinning s speed to the auger, a cord 88is provided, such cord being secured to one end of handle 86 and thenmovingly connected to the derrick structure 12 and then extendeddownwardly toward ground level. rIherefore by merely pulling down oncord 88 which can be accomplished from ground level, the transmission 24can be readily shifted into spinning speed, and upon release of thecord, the torsion spring 84 actuates rod 80 and associated shifting fork78 to automatically move coupling gear collar 58 downwardly intocoupling relation between gear 52 and the aforementioned gear element 64rotatably mounted on the transmission shaft 54. The lengthwise axis ofthe operating handle 86 in such normal non-actuated position isillustrated by the dot-dash line 86a in FlG. 3.

Gear 64 constitutes the sun gear of a second speed reduction unit 92,the latter comprising sun gear 64, planetary gears 94 rotatably mountedon rotatable planetary carrier structure 94a, and a ring gear 96,secured as by means of dowel pins 96a to housing 38. It will be seentherefore that change gear collar S normally couples gear 52 to speedreduction unit 92, unless shifted into spinning speed operation byactuation of cord 88 and associated handle 86.

Also attached to planetary carrier structure 94a are a plurality ofcurved lube vanes 93 (FIGS. 3 and 5) which revolve with the gearreduction unit 92 and splash liquid lubricant, such as oil, contained incasing 3S upwardly against the top wall 43 of housing 38 from whence itdrains down to lubricate the parts of the transmission disposed in theupper portion of the housing. An oil collecting device 100, mounted onthe top of the iirst planet-ary speed reduction unit 51 collects suchsplashed oil and aids in lubricating the upper portions of thetransmission.

Secured to planetary carrier structure 04a is an underlying speed changegear 102 for rotation with such carrier structure. Disposed below gear102 and rotatably mounted with respect to transmission shaft 54 is a sungear 104. Sun gear 104 constitutes a part speed reduction unit 105, thelatter unit being comprised of sun gear 104, planetary gear 106 (FIGS. 3and 6) rotatably mounted as at 107 on rotatable planetary carrierstructure S, and an internal ring gear 110, which in the embodimentshown is formed as a unit with housing portion 38b of the sectionaltransmission housing 38.

Planetary carrier structure 108 is drivingly coupled to transmissionshaft 54 as at 112, and it will be seen therefore that upon powerrotation of such planetary carrier structure 108, the outputtransmission shaft 54 will be driven thereby.

An axially movable slidable change gear collar 114 (FIGS. 3 and 8) isprovided for selectively coupling gear 102 on speed reduction unit 92 tosun gear 104 of speed reduction unit 105, or coupling gear 102 to gearportion 116 on planetary carrier structure 108 of speed reduction unit105.

When slidable gear collar 114 is in coupled relation between gear 102and sun gear 104, and as shown in FIG. 3 of the drawings, thetransmission is positioned for high torque, low digging speed operation,with the power from gear 102 being fed to sun gear 104, planetary gears106 to planetary carrier structure 108 and thence to transmission shaft54 by way of connection 112. This relatively low speed high torquearrangement is for use during diiicult digging operations, such as inhard soil conditions or when a larger size auger is being used to drilla bigger hole.

`Referring now to FIG. 8, which illustrates in vertical section thesliding gear collar 114, it will be seen that the latter comprisesspaced internal gear teeth 118 and 120 at opposite ends thereof andexternal gear teeth 122 on the lower end thereof. It also embodies acircumferentially extending groove 124 which receives shifter forkelement 126 (FIG. 6) for actuating the gear collar. Shifting forkelement 126 comprises a cylindrical, sleeve portion 126a of the thirdplanetary which is rotatably mounted on transverse operating rod 128which in turn is rotatably journaled as at 130 in casing portion 38h.One end of the rod 128 has a control handle element 132 (FIGS. 1, 2 and6) secured thereto. An anchor member 133 is secured as at 133a to rod128 and a helical torsion spring 133b is provided, one end of which issecured to anchor member 133 and the other end of which is secured tosleeve portion 126a, the purpose of such an arrangement beinghereinafter described.

In accordance with the invention, means is provided for yieldablyretaining handle element 132 in a selected digging speed position, or inother words retaining change gear coupling collar 114 in coupledrelation between gear 102 and sun gear 104, gear 102 and gear portion116 on planetary carrier structure 103. This means takes the form of aspring loaded detent 136 (FIGS. 9 and 10) mounted on the upper portionof a handle 132 and adapted for holding coaction in one or the other ofrecesses 140, 140e disposed in a plate 142 secured to the exterior ofhousing portion 138b. Thus it will be seen that means is provided foryieldably resisting lfree pivotal movement of operating handle 132, tothereby retain the change gear collar 114 in its selected couplingposition.

If, handle 132 is pivoted so that the detent 136 is in retainingcoaction with recess 140e and with the length- Wise axis of the handle132 in the position illustrated by dot-dash line X in FIG. 9 and thusshifting coupling collar 114 into coupling relation between gear 102 andgear portion 116 on planetary carrier structure 108, then the power fromthe gear 102 is transmitted through carrier structure 10S direct totransmission shaft 54 via connection 112, to provide a medium torquenormal digging speed for the auger. This speed is for use for digging ordrilling holes in conventional types of soils, and represents the speedfor which the earth boring apparatus is conventionally adapted for use.its such shifting movement of collar 114.

Referring now again to FIGS. 6, 9 and 10, the com pression spring 143 ofspring loaded detent 136 is stronger than the torsion spring 133]), sothat when handle 132 is moved from low digging speed position to higheror normal digging speed position or vice versa, the operating handle 132will be retained in its new selected position even though shiftingcollar 114 might be tightly meshed with gears 102 and 104, or with gears102 and 116, thereby preventing the desired shifting movement of collar114. In such event, torsion spring 133b will be deflected as rod 128rotates thereby applying a force on shifter fork 126 via sleeve portion126a. Then when the load is subsequently removed from the gear train byeither a forward or reverse motion of motor unit 41,` automaticalthecoupling collar 114 will be freed up to ly move into meshing relationwith the speed gear (Le. gear 104 or 116) selected, due to the forcebeing applied by dellected torsion spring 133b, to thereby provide asemi-automatic gear shifting arrangement. It will be seen .thereforethat with such an arrangement it is not necessary to immediatelyaccomplish digging speed shifting of the transmission upon actuation ofthe contro-l lever or handle 132, but such is automatically accomplishedsubsequently upon subsequent actuation of the motor power unit.

A feature of the invention in the FIG. 3 embodiment is that if sodesired, the housing portion 38b and its associated speed reduction unit105 and accompanying sliding coupling collar 114 may be readily removedby merely removing bolt and nut assemblies 144 which hold the latter.transmission section in assembled relation with the main housing portion33. Thereupon, after replacing transmission shaft 54 with a shaft tosuit so as to couple gear 102 to the shaft and then attach bottom coverplate 146 directly to the ange portion 148 of the main housing 38, asmaller more compact lower cost a horizontally extending,

or in coupling relation between A stop 141 lim-y spaanse powertransmission unit will be provided, which will possess theaforementioned auger spinning speed and a single digging speed. It willbe seen that such an arrangement will be readily accomplished with thestructure shown and without any necessity for a reconstruction or theupper portion of the transmission gear train arrange-ment.

Referring now to FIGS. l1 to 13 inclusive of the drawings, there isshown a modiiication of the invention. This modifica-tion operatesgenerally similarly to the rst described embodiment and possesses aspinning speed and two digging speeds (a high torque, relatively lowspeed and a medium torque normal or higher speed) the Same as in the-tirst described embodiment, but does not possess the feature wherebythe transmission unit can be readily revised into a single digging speeduni-t, as discussed immediately above, and in addition utilizes adifferent arrangement of means for yieldably retaining the operatingshift handle, which controls the digging speeds of the earth boringapparatus, in its selected positions.

Referring now to FIG. l1, the rotary, fluid powered motor unit 41 ismounted on the top cover plate 15@ of the power transmission unit 24 andoutput shaft 150e thereof extends into the transmission chamber definedby the housing member 152. A pinion gear 154 is secured to the outputshaft 150e of the motor and is disposed in meshing relation with a spurgear 156 rotatably mounted on transmission shaft 54. Spur gear 156 has agear portion 15651 secured thereto, and immediately below gear portion1560. there is disposed a speed change gear 158 fixed to thetransmission shaft. 1t will be seen therefore that pinion gear 154, spurgear 156 and gear 156:1 comprise a speed reduction unit 157 of thetransmission. A coupling gear collar 160 of the same general arrangementas collar 58 of the iirst described ernbodiment is provided -forselectively coupling gear 15611 to either gear 158 ixed to transmissionshaft 54 or to sun gear 162 of the second speed reduction unit 164. Ifthe collar 160 is moved upwardly from the position shown into couplingarrangement between gear 156e and gear 158, the aforediscussed highspinning speed for the auger is provided. The position of the couplingcollar 160 shown in FIG. 11 is the normal position therefor, and ashifter fork element 78, operating rod 80 associated torsion spring 84,and operating handle 86, the Same as in the first described embodiment,is provided for shifting coupling collar 160 from the position showninto its auger spinning speed position, and for automatically returningthe collar 160 and associated control lever to normal coupling position,upon release of the operating handle.

It will be seen therefore that the coupling collar 160 is normally heldout of spinning speed position, the same as in the iirst describedembodiment of the invention, and Y the operating handle 86 therefor maybe provided with acord for operating the handle from ground level, thesame as in the first described embodiment of the invention.

When the coupling collar 160 is in the coupling position shown in FIG.1l, or in other words coupling gear 156a to sun gear 162 of theplanetary gear speed reduction unit 164, the power is transmitted fromgear 156e .through gear reduction unit 16d` to the gear 168 formedintegrally with the planetary carrier structure 170 of reduction unit164, and being rotatably mounted with re spect to transmission shaft 54.

A coupling collar member 172 which is substantially identical to collar114 of the first described embodiment of the invention is provided forselectively coupling gear 168 to sun gear 174 of the planetary speedreduction unit 176. or to the internal tooth gear portion 178 of theplanetary carrier structure 188 of speed reduction unit 176, the latterunit construction to the planetary speed reduction 'unit 105 of thefirst described embodiment, except that the internal being substantiallyidentical in ring gear portion 182 of reduction unit 176 is not formedas a unit with the transmission housing 152, as is the internal ringgear of the first described embodiment. In all other respects however,it is substantially identical.

When coupling collar 172 is in the position shown in FIG. 11, or inother words is coupling gear 168 to sun gear 174 of unit 176, arelatively high torque low auger digging speed is provided, for use asaforementioned in ditiicult digging conditions such as hard soils orwhen using a larger sized auger. When collar 172 is moved downwardlyinto coupling relation between gear 168 and gear portion 178 onplanetary carrier structure 180, a medium torque, normal digging speedis provided as in therst described embodiment, for use underconventional digging conditions, with the planetary carrier structure180 being secured to the transmission shaft 54 as at 112, the same as inthe first described embodiment of the invention.

An operating handle 186 (FIGS. 11 and 12) is provided for actuating thecontrol shaft 18S on which is rotatably mounted a shifter fork element190 the same as in the first described embodiment, with fork element 190coacting in the circumferential external slot 192 of sliding collar 172for shifting the collar from one to the other of its digging speedpositions. A torsion spring 194 is provided coacting between therotatable sleeve portion 196 of shifter fork 190 and the shaft 188, thesame as in the first described embodiment to make the shifting of collar172 a semi-automatic operation the same as in the first describedembodiment.

Means 19S is also provided for yieldably retaining the operating handle186 in the selected digging speed position.

In this embodiment of the invention, such means takesV the form of anover-center spring mechanism comprising a pin 200 projecting from theexterior of housing 152 and a pin 202 mounted on the innerside of handle186. An elongated guide member 204 is pivotally mounted on pin 200 andan elongated guide member 206 is pivotally mounted on pin 202 and inaxially movable relation to guide 204, and a compression spring 208encircling such guide members is disposed intermediate abutments 209mounted on the respective guide members. Spring 208 is stronger thantorsion spring 194 and thus maintains the operating lever 186 in eitherof the selected digging positions, with the spacing between abutments209 decreasing against the resistance of spring 208 upon pivotingofhandle 186 from one digging speed position to the other digging speedposition, and as can be best seen from FIG. 13 of the drawings, whilethe distance between the axis of rotation of rod 188 and the axis of pin202 remaining the same during such pivlotal movement of the operatinghandle 186'. As can be seen from FIG. 13 of the drawings, the axis ofspring 208 is normally disposed obliquely with respect to a planepassing through the pivotal axis of lever 186 and the axis of pin 202,in either of the levers digging'speed settings.

Carrier structure 180 of speed reduction unit 176 also carries curvedlube vanes 212A to splash lubricant up against the top cover plate 150,especially during the spinning speed of the transmission, for eliectivelubrica-V tion of the upper portion of the gear train and bearings 214rotatably mounting shaft 54. A deliecting groove 216 is provided in topcoverplate150 for detlecting such splashed lubricant downwardly intoupwardly facing concave face 218 While gear 156 is revolving, the latteris provided with a reverse draft 220 on the upper section of its outerrim to thereby in effect form a circular storage chamber which retainsthe liquid lubricant until the rotary motion stops, at which time thelubricant drains toward center down through the bearings.

From the foregoing description and accompanying drawings it will be seenthat the invention provides a novel, compact, multiple speed earthboring apparatus which incorporates a spinning or rapid speed for throwfing off borings which may adhere to the auger after withdrawal from thedrilled hole, as well as a plurality of digging speeds for effective useof the apparatus under varying digging conditions or with differentsizes of augers. The invention also provides an earth boring apparatusof the above type which incorporates means for yieldably retaining thegear shifting apparatus in the desired Vsetting and providing asemi-automatic shifting operation upon actuation of the digging speedcontrol lever as well as an apparatus which may be easily revised into areduced speed unit of relatively smaller size and lower cost, withoutthe necessity of materially reconstructing the apparatus. The inventionalso provides an earth boring apparatus of the above type which isadapted to be actuated by pressurized fiuid power for effective andsmooth ground drilling operations.

The terms and expressions which have been used are used as terms ofdescription and not of limitation and there is no intention in the useof such terms and expressions of excluding any equivalents of any of thefeatures shown and described or portions thereof, but it is recognizedthat various modifications are possible within the scope of theinvention claimed. Y I claim: v

1. In an earth boring apparatus ofthe type adapted for mounting on aderrick carried by a -vehicle for ready portability thereof, thecombination including a speedchange geared transmission unit includingan external housing, means on said housing 4foro peratively mountingsaid unit on the derrick, said unit vkincluding anroutput shaft, anearth boring auger operatively coupled` to said transmission shaft andadapted to be rotated at a' speed determined by said transmission unit,a fiuid powered rotary type motor mounted onsaid housing and includingan output shaft extending into the interior of said housing, a firstgeared speed reduction unit rotatably mounted on said output shaftinteriorally of said housing and being in coupled relation with vsaidmotor, means for selectively coupling said first speed reduction unittoV said transmission shaft whereby the latter is rotatedat a highspinning speed for throwing off borings which may adhere to said auger,control means for actuating said last mentioned coupling means, saidcontrol means including means for yieldably urging said coupling meansout of coupling relation between said shaft and said first speedreduction unit, a second planetary type geared speed reduction unitrotatably mounted on said transmission shaft, said coupling means beingnormally disposed in coupling relation between said first speedreduction unit and second speed reduction unit, a third planetary typegeared speed reduction unit including a sun gear and rotary planetarygear carrier structure, said planetary gear carrier structure of saidthird speed reduci tion unit being secured to said transmission shaftfor rotition therewith, second coupling means selectively coupleablebetween said second speed reduction unit and said sun gear and betweensaid second speed reduction unit and said planetary gear carrierstructure wherebysaid transmission shaft is provided with a mediumtorque normal digging speed and a high torque lower digging speeddepending on the coupling position of second coupling means, controlmeans for selectively actuating said second coupling means to either ofits digging speed coupling positions, and means for yieldably retainingsaid second control means in its selected position.

2. In an earth boring apparatus in accordance with claim l includingvane means fixed to one of said speed reduction units for rotationtherewith and adapted to splash lubricant upwardly from the lowerportion of said transmission housing to the upper portion thereof forlubricating the various parts of said transmission unit.

3. A multiple-speed compact geared transmission unit adapted for usewith a portable earth boring auger for driving the latter at variousspeeds comprising in combination, a housing, a transmission output shaftadapted for connection to said earth boring auger, said transmissionunit being adapted to be activated by a high speed rotary fiud poweredmotor, a tirst geared speed'reduction unit rotatably mounted on saidtransmission shaft and adapted to be coupled to said motor, a secondgeared speed reduction unit rotatably mounted on said transmissionshaft, a shifting coupling element normally coupling said first speedvreduction unit to second speed reduction unit, said coupling elementbeing shiftable into coupling relation between first speed reductionunit and said transmission shaft, control means movable from an inactiveto an active position for so shifting said coupling element, saidcontrol means including resilient means for yieldably resisting shiftingof said coupling element and for automatically returning said controlmeans to inactive position and thus returning said coupling element intocoupling relation between said first speed reduction unit and saidsecond speed vreduction unit, a third speed reduction unit drivinglycoupled to. said transmission shaft, said third speed reduction. unitincluding means for providing a medium torque normal digging speed forsaid transmission shaft and a higher torque lower digging speed for saidtransmission shaft, a second shifting coupling element coacting betweensaid second speed reductionunit and said third speed. reduction unitfor'driving said transmission shaft at either of its selected diggingspeeds, control means for actuating said second coupling element intoeither of its coupling positions, and means, for yieldably retainingsaid secondc'ontrol means in its selected position. t

4.- A transmission unit in accordancef with claim 3 where in said secondcontrol means includes arotatable operating shaft `extendingtransversely of `said sousing, av

shifter fork element pivotally mounted on said operating shaft, aneXteriorally accessible pivotal operating handle for rotating saidoperating ing between said shifter fork and said operating lshaft foractuation of said shifter fork upon rotation of said operatingV shaft,said shifter fork being operatively coupled to said second couplingelement for actuation thereof into either of its digging speed couplingpositions, said retaining means for said second control meanscornprising a compression spring having a greater capacity than saidtorsion spring and coacting with said handle to maintain the latter inits selected digging speed setting, said torsion spring upon deflectionthereof by pivoting of said handle operating to actuate said secondcoupling element to its desired digging .speed coupling positionsequentially with pivoting of said handle and actuation of said speedreduction units whereby a semiautomatic shifting of said second couplingelement is accomplished. Y

5. In an earth boring apparatus of the type adapted forsuspension-mounting on a derrick carried by a vehicle, the combinationcomprising a change speed gear transmission unitIincluding an outputshaft, a rotary fluid powered motor mounted on said unit and operativelycoupled to said unit for actuating the same, said output shaft beingadapted to be coupled to an earth boring auger for rotation of thelater,said unit comprising first gear means coupled to said motor, second gearmeans drivingly engageable with said shaft, coupling means selectivelymovable to connect the first gear means and the shaft for providing arelatively high spinning speed for the auger, or to couple said firstgear means to said second geartmeans for providing at least one diggingspeed to the shaft, control means for shifting said coupling means,spring means connected to said control means normally urging saidcoupling means to a position for coupling said first gearmeans to saidsecond gearl shaft, a torsion spring coact 1i,..\, ,.V.,.'r uan.' earthboring apparatusv of, the type ',adapted iorwsuspen'sion 'mounting onladerrick` carried by.v a vebif 'Cl ,L the, cbmlgirxatitzn;.'compris'insa change speedsear, transmission unit including :an outputshaft, a rotary fluid. poweredfumotoif mofuntedjon saidu'unit andoperatively coupled lto 'saidnnit for actuating the esame, said outputsharftj being adapted .to be coupledtofa'n 'earth-boring auger vfo'rjrotation offthe`latter, said transmission unit comprising lirst gearmeans coupledrto-said motor, second 4geaifmeans- .adapted to provide alplurality of digging speeds` to saidshaft,4 lirst vcoupling meansbetween the irstgearumeans and the .shaft and between said first andsecond gear means, adapted toselectively 4couple said first, gear`ilrieansv to ,said shaft for Aproviding a relatively high spinning speedfortheauger or tocouple said first gear means tovsaid second gearmeans,second coupling means selectively operable Vto, adjust said second gearmeans to provideav desireddigging speed at whichthe auger will operatdnacontrol means for. shifting said second coul pling means, asecondcontrol means for shifting said iirst coupling means, spring meansconnected to said sec-v ond control means normally urging said rstcoupling means to va position for coupling said first gear means to saidsecond gear means, and means for, shifting said secondcontrol means toaposition to connect said rst gearmeans to said shaft against; ltheaction of `said spring means. r

' 7l n earth .boring apparatus in accordance with claim 61;, whereinlthe first .mentioned control means includes meansfor yieldablyretaining said iirst controimeans in its selected setting.

" 8. Ayn earth ,bormgapparatus in accordance with` claim'-7`whereii1'said irst control means, includes. an operating lhandleexternallyacessible of saidtransmission unit and` said retaining meansycomprises a springloaded detent Y operative ,between said handle and theexterior of' said transmission v*unit 'and'engageable in complementary,re

cesses defining the ,operating positions ofrthejhandle fork j providingthe various digging speeds for said auger.

j An earth bormg'apparatus in accordance with claimvl wherein s'aidiirst control means includes, an operating 'handle pivtally mounted withrespect tothe exterior of Vsaid"tr'ai'i'sinission unit,' said retainingmeans comprisingw l a resilient member of the compression type coactingbef tweenffan abutment on the exterior of said transmis-sionA Y v;andan'abutinent on said handle, said abutmentsbeing in spaced relationto the pivotal axis of said handles, -said resilient `memberbeingnormally disposed in generallyh dbliquefrelationwith respectto thelengthwise axis of said L rlhtiixiile` a. l l Y 1-O.I`n an earthrborin'gapparatus ot the type .adapted for suspension ymounting-on .a -der rickcarried by a-vehisl cle', the combination comprising a change speed geartrans-,- mission unit includinganrexternal housinganda remove--` ableoutput shaft` disposed in saidhousing,V said housing being of sectionalconstruction comprising an upper'por; tion .and alower portion, saidshaft being adaptedfon coupling to an earth boring auger for drivingythe latter, said transmissionunit being. adapted to be.v activated by ahigh speed rotary fluid powered motor, the latter being adapted to besupported by said unit, said transmission unit comprising a first gearassembly mounted on said shaftand being adapted for, coupled relation tothe motor, shiftable means for selectively coupling said first as-zsembly to said shaft for providing a relatively high spin-4 ning speedfor the auger for throwing olf borings which may adhere to the auger,control means for actuating said: last mentioned coupling means, asecond gear assembly rotatably mounted on said shaft, said couplingmeans normally coupling said first assembly to said second assembly,said first and second assemblies being disposed k assembly disposed insaid lower portion of said housing,

said third assembly including means coupling said third assembly to saidshaft, second coupling Ameans selectivelyl operable between said secondand said third assemblies to `provide a ,plurality of digging speeds forsaidshaft,

1 whereby the latter isprovided with amedium torque normal digging speedand a higher torque lower digging speed dependingon the position of saidsecond coupling means, control means Jfor selectively actuating saidsecond coupling means, the lastmentioned controlmeans includ- 1 ing ahandlev member mounted on the exterior of said lower portion of saidhousing, means detachably con-` necting said housing sections togetherwhereby said lower housing section and associated third gear assemblyand said last mentioned control means and associated second couplingmeansrand said shaft maybe removed, and a second shaft -adapted toreplace'said first mentioned shalt,

saidreplaceable shaft being of reduced length and' hav-l ing meansthereon adapted vtoqbe coupled to said gear means of said secondgear;assembly and vto' said iirst gear nassembly.l Y Jv .e

-References Cited inethefile ofthis. pate-nt l UNITEDJSTALTESPATENTS

